lua/ubus.c

   1 /*
   2  * Copyright (C) 2012 Jo-Philipp Wich <jow@openwrt.org>
   3  * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <unistd.h>
  16 #include <libubus.h>
  17 #include <libubox/blobmsg.h>
  18 #include <libubox/blobmsg_json.h>
  19 #include <lauxlib.h>
  20
  21
  22 #define MODNAME        "ubus"
  23 #define METANAME       MODNAME ".meta"
  24
  25 static lua_State *state;
  26
  27 struct ubus_lua_connection {
  28         int timeout;
  29         struct blob_buf buf;
  30         struct ubus_context *ctx;
  31 };
  32
  33 struct ubus_lua_object {
  34         struct ubus_object o;
  35         int r;
  36 };
  37
  38 static int
  39 ubus_lua_parse_blob(lua_State *L, struct blob_attr *attr, bool table);
  40
  41 static int
  42 ubus_lua_parse_blob_array(lua_State *L, struct blob_attr *attr, int len, bool table)
  43 {
  44         int rv;
  45         int idx = 1;
  46         int rem = len;
  47         struct blob_attr *pos;
  48
  49         lua_newtable(L);
  50
  51         __blob_for_each_attr(pos, attr, rem)
  52         {
  53                 rv = ubus_lua_parse_blob(L, pos, table);
  54
  55                 if (rv > 1)
  56                         lua_rawset(L, -3);
  57                 else if (rv > 0)
  58                         lua_rawseti(L, -2, idx++);
  59         }
  60
  61         return 1;
  62 }
  63
  64 static int
  65 ubus_lua_parse_blob(lua_State *L, struct blob_attr *attr, bool table)
  66 {
  67         int len;
  68         int off = 0;
  69         void *data;
  70         char buf[32];
  71
  72         if (!blobmsg_check_attr(attr, false))
  73                 return 0;
  74
  75         if (table && blobmsg_name(attr)[0])
  76         {
  77                 lua_pushstring(L, blobmsg_name(attr));
  78                 off++;
  79         }
  80
  81         data = blobmsg_data(attr);
  82         len = blobmsg_data_len(attr);
  83
  84         switch (blob_id(attr))
  85         {
  86         case BLOBMSG_TYPE_BOOL:
  87                 lua_pushboolean(L, *(uint8_t *)data);
  88                 break;
  89
  90         case BLOBMSG_TYPE_INT16:
  91                 lua_pushinteger(L, be16_to_cpu(*(uint16_t *)data));
  92                 break;
  93
  94         case BLOBMSG_TYPE_INT32:
  95                 lua_pushinteger(L, be32_to_cpu(*(uint32_t *)data));
  96                 break;
  97
  98         case BLOBMSG_TYPE_INT64:
  99                 /* NB: Lua cannot handle 64bit, format value as string and push that */
 100                 sprintf(buf, "%lld", (long long int) be64_to_cpu(*(uint64_t *)data));
 101                 lua_pushstring(L, buf);
 102                 break;
 103
 104         case BLOBMSG_TYPE_STRING:
 105                 lua_pushstring(L, data);
 106                 break;
 107
 108         case BLOBMSG_TYPE_ARRAY:
 109                 ubus_lua_parse_blob_array(L, data, len, false);
 110                 break;
 111
 112         case BLOBMSG_TYPE_TABLE:
 113                 ubus_lua_parse_blob_array(L, data, len, true);
 114                 break;
 115
 116         default:
 117                 lua_pushnil(L);
 118                 break;
 119         }
 120
 121         return off + 1;
 122 }
 123
 124
 125 static bool
 126 ubus_lua_format_blob_is_array(lua_State *L)
 127 {
 128         lua_Integer prv = 0;
 129         lua_Integer cur = 0;
 130
 131         /* Find out whether table is array-like */
 132         for (lua_pushnil(L); lua_next(L, -2); lua_pop(L, 1))
 133         {
 134 #ifdef LUA_TINT
 135                 if (lua_type(L, -2) != LUA_TNUMBER && lua_type(L, -2) != LUA_TINT)
 136 #else
 137                 if (lua_type(L, -2) != LUA_TNUMBER)
 138 #endif
 139                 {
 140                         lua_pop(L, 1);
 141                         return false;
 142                 }
 143
 144                 cur = lua_tointeger(L, -2);
 145
 146                 if ((cur - 1) != prv)
 147                 {
 148                         lua_pop(L, 1);
 149                         return false;
 150                 }
 151
 152                 prv = cur;
 153         }
 154
 155         return true;
 156 }
 157
 158 static int
 159 ubus_lua_format_blob_array(lua_State *L, struct blob_buf *b, bool table);
 160
 161 static int
 162 ubus_lua_format_blob(lua_State *L, struct blob_buf *b, bool table)
 163 {
 164         void *c;
 165         bool rv = true;
 166         const char *key = table ? lua_tostring(L, -2) : NULL;
 167
 168         switch (lua_type(L, -1))
 169         {
 170         case LUA_TBOOLEAN:
 171                 blobmsg_add_u8(b, key, (uint8_t)lua_toboolean(L, -1));
 172                 break;
 173
 174 #ifdef LUA_TINT
 175         case LUA_TINT:
 176 #endif
 177         case LUA_TNUMBER:
 178                 blobmsg_add_u32(b, key, (uint32_t)lua_tointeger(L, -1));
 179                 break;
 180
 181         case LUA_TSTRING:
 182         case LUA_TUSERDATA:
 183         case LUA_TLIGHTUSERDATA:
 184                 blobmsg_add_string(b, key, lua_tostring(L, -1));
 185                 break;
 186
 187         case LUA_TTABLE:
 188                 if (ubus_lua_format_blob_is_array(L))
 189                 {
 190                         c = blobmsg_open_array(b, key);
 191                         rv = ubus_lua_format_blob_array(L, b, false);
 192                         blobmsg_close_array(b, c);
 193                 }
 194                 else
 195                 {
 196                         c = blobmsg_open_table(b, key);
 197                         rv = ubus_lua_format_blob_array(L, b, true);
 198                         blobmsg_close_table(b, c);
 199                 }
 200                 break;
 201
 202         default:
 203                 rv = false;
 204                 break;
 205         }
 206
 207         return rv;
 208 }
 209
 210 static int
 211 ubus_lua_format_blob_array(lua_State *L, struct blob_buf *b, bool table)
 212 {
 213         for (lua_pushnil(L); lua_next(L, -2); lua_pop(L, 1))
 214         {
 215                 if (!ubus_lua_format_blob(L, b, table))
 216                 {
 217                         lua_pop(L, 1);
 218                         return false;
 219                 }
 220         }
 221
 222         return true;
 223 }
 224
 225
 226 static int
 227 ubus_lua_connect(lua_State *L)
 228 {
 229         struct ubus_lua_connection *c;
 230         const char *sockpath = luaL_optstring(L, 1, NULL);
 231         int timeout = luaL_optint(L, 2, 30);
 232
 233         if ((c = lua_newuserdata(L, sizeof(*c))) != NULL &&
 234                 (c->ctx = ubus_connect(sockpath)) != NULL)
 235         {
 236                 ubus_add_uloop(c->ctx);
 237                 c->timeout = timeout;
 238                 memset(&c->buf, 0, sizeof(c->buf));
 239                 luaL_getmetatable(L, METANAME);
 240                 lua_setmetatable(L, -2);
 241                 return 1;
 242         }
 243
 244         /* NB: no errors from ubus_connect() yet */
 245         lua_pushnil(L);
 246         lua_pushinteger(L, UBUS_STATUS_UNKNOWN_ERROR);
 247         return 2;
 248 }
 249
 250
 251 static void
 252 ubus_lua_objects_cb(struct ubus_context *c, struct ubus_object_data *o, void *p)
 253 {
 254         lua_State *L = (lua_State *)p;
 255
 256         lua_pushstring(L, o->path);
 257         lua_rawseti(L, -2, lua_objlen(L, -2) + 1);
 258 }
 259
 260 static int
 261 ubus_lua_objects(lua_State *L)
 262 {
 263         int rv;
 264         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 265
 266         lua_newtable(L);
 267         rv = ubus_lookup(c->ctx, NULL, ubus_lua_objects_cb, L);
 268
 269         if (rv != UBUS_STATUS_OK)
 270         {
 271                 lua_pop(L, 1);
 272                 lua_pushnil(L);
 273                 lua_pushinteger(L, rv);
 274                 return 2;
 275         }
 276
 277         return 1;
 278 }
 279
 280 static int
 281 ubus_method_handler(struct ubus_context *ctx, struct ubus_object *obj,
 282                 struct ubus_request_data *req, const char *method,
 283                 struct blob_attr *msg)
 284 {
 285         struct ubus_lua_object *o = container_of(obj, struct ubus_lua_object, o);
 286
 287         lua_getglobal(state, "__ubus_cb");
 288         lua_rawgeti(state, -1, o->r);
 289         lua_getfield(state, -1, method);
 290
 291         if (lua_isfunction(state, -1)) {
 292                 lua_pushlightuserdata(state, req);
 293                 if (!msg)
 294                         lua_pushnil(state);
 295                 else
 296                         ubus_lua_parse_blob_array(state, blob_data(msg), blob_len(msg), true);
 297                 lua_call(state, 2, 0);
 298         }
 299         return 0;
 300 }
 301
 302 static int lua_gettablelen(lua_State *L, int index)
 303 {
 304         int cnt = 0;
 305
 306         lua_pushnil(L);
 307         index -= 1;
 308         while (lua_next(L, index) != 0) {
 309                 cnt++;
 310                 lua_pop(L, 1);
 311         }
 312
 313         return cnt;
 314 }
 315
 316 static int ubus_lua_reply(lua_State *L)
 317 {
 318         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 319         struct ubus_request_data *req;
 320
 321         luaL_checktype(L, 3, LUA_TTABLE);
 322         blob_buf_init(&c->buf, 0);
 323
 324         if (!ubus_lua_format_blob_array(L, &c->buf, true))
 325         {
 326                 lua_pushnil(L);
 327                 lua_pushinteger(L, UBUS_STATUS_INVALID_ARGUMENT);
 328                 return 2;
 329         }
 330
 331         req = lua_touserdata(L, 2);
 332         ubus_send_reply(c->ctx, req, c->buf.head);
 333
 334         return 0;
 335 }
 336
 337 static int ubus_lua_load_methods(lua_State *L, struct ubus_method *m)
 338 {
 339         struct blobmsg_policy *p;
 340         int plen;
 341         int pidx = 0;
 342
 343         /* get the function pointer */
 344         lua_pushinteger(L, 1);
 345         lua_gettable(L, -2);
 346
 347         /* get the policy table */
 348         lua_pushinteger(L, 2);
 349         lua_gettable(L, -3);
 350         plen = lua_gettablelen(L, -1);
 351
 352         /* check if the method table is valid */
 353         if ((lua_type(L, -2) != LUA_TFUNCTION) ||
 354                         (lua_type(L, -1) != LUA_TTABLE) ||
 355                         lua_objlen(L, -1) || !plen) {
 356                 lua_pop(L, 2);
 357                 return 1;
 358         }
 359
 360         /* store function pointer */
 361         lua_pushvalue(L, -2);
 362         lua_setfield(L, -6, lua_tostring(L, -5));
 363
 364         /* setup the policy pointers */
 365         p = malloc(sizeof(struct blobmsg_policy) * plen);
 366         memset(p, 0, sizeof(struct blobmsg_policy) * plen);
 367         m->policy = p;
 368         lua_pushnil(L);
 369         while (lua_next(L, -2) != 0) {
 370                 int val = lua_tointeger(L, -1);
 371
 372                 /* check if the policy is valid */
 373                 if ((lua_type(L, -2) != LUA_TSTRING) ||
 374                                 (lua_type(L, -1) != LUA_TNUMBER) ||
 375                                 (val < 0) ||
 376                                 (val > BLOBMSG_TYPE_LAST)) {
 377                         lua_pop(L, 1);
 378                         continue;
 379                 }
 380                 p[pidx].name = lua_tostring(L, -2);
 381                 p[pidx].type = val;
 382                 lua_pop(L, 1);
 383                 pidx++;
 384         }
 385
 386         m->n_policy = pidx;
 387         m->name = lua_tostring(L, -4);
 388         m->handler = ubus_method_handler;
 389         lua_pop(L, 2);
 390
 391         return 0;
 392 }
 393
 394 static struct ubus_object* ubus_lua_load_object(lua_State *L)
 395 {
 396         struct ubus_lua_object *obj = NULL;
 397         int mlen = lua_gettablelen(L, -1);
 398         struct ubus_method *m;
 399         int midx = 0;
 400
 401         /* setup object pointers */
 402         obj = malloc(sizeof(struct ubus_lua_object));
 403         memset(obj, 0, sizeof(struct ubus_lua_object));
 404         obj->o.name = lua_tostring(L, -2);
 405
 406         /* setup method pointers */
 407         m = malloc(sizeof(struct ubus_method) * mlen);
 408         memset(m, 0, sizeof(struct ubus_method) * mlen);
 409         obj->o.methods = m;
 410
 411         /* setup type pointers */
 412         obj->o.type = malloc(sizeof(struct ubus_object_type));
 413         memset(obj->o.type, 0, sizeof(struct ubus_object_type));
 414         obj->o.type->name = lua_tostring(L, -2);
 415         obj->o.type->id = 0;
 416         obj->o.type->methods = obj->o.methods;
 417
 418         /* create the he callback lookup table */
 419         lua_createtable(L, 1, 0);
 420         lua_getglobal(L, "__ubus_cb");
 421         lua_pushvalue(L, -2);
 422         obj->r = luaL_ref(L, -2);
 423         lua_pop(L, 1);
 424
 425         /* scan each method */
 426         lua_pushnil(L);
 427         while (lua_next(L, -3) != 0) {
 428                 /* check if it looks like a method */
 429                 if ((lua_type(L, -2) != LUA_TSTRING) ||
 430                                 (lua_type(L, -1) != LUA_TTABLE) ||
 431                                 !lua_objlen(L, -1)) {
 432                         lua_pop(L, 1);
 433                         continue;
 434                 }
 435
 436                 if (!ubus_lua_load_methods(L, &m[midx]))
 437                         midx++;
 438                 lua_pop(L, 1);
 439         }
 440
 441         obj->o.type->n_methods = obj->o.n_methods = midx;
 442
 443         /* pop the callback table */
 444         lua_pop(L, 1);
 445
 446         return &obj->o;
 447 }
 448
 449 static int ubus_lua_add(lua_State *L)
 450 {
 451         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 452
 453         /* verify top level object */
 454         if (lua_istable(L, 1)) {
 455                 lua_pushstring(L, "you need to pass a table");
 456                 lua_error(L);
 457                 return 0;
 458         }
 459
 460         /* scan each object */
 461         lua_pushnil(L);
 462         while (lua_next(L, -2) != 0) {
 463                 struct ubus_object *obj = NULL;
 464
 465                 /* check if the object has a table of methods */
 466                 if ((lua_type(L, -2) == LUA_TSTRING) && (lua_type(L, -1) == LUA_TTABLE)) {
 467                         obj = ubus_lua_load_object(L);
 468
 469                         if (obj)
 470                                 ubus_add_object(c->ctx, obj);
 471                 }
 472                 lua_pop(L, 1);
 473         }
 474
 475         return 0;
 476 }
 477
 478 static void
 479 ubus_lua_signatures_cb(struct ubus_context *c, struct ubus_object_data *o, void *p)
 480 {
 481         lua_State *L = (lua_State *)p;
 482
 483         if (!o->signature)
 484                 return;
 485
 486         ubus_lua_parse_blob_array(L, blob_data(o->signature), blob_len(o->signature), true);
 487 }
 488
 489 static int
 490 ubus_lua_signatures(lua_State *L)
 491 {
 492         int rv;
 493         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 494         const char *path = luaL_checkstring(L, 2);
 495
 496         rv = ubus_lookup(c->ctx, path, ubus_lua_signatures_cb, L);
 497
 498         if (rv != UBUS_STATUS_OK)
 499         {
 500                 lua_pop(L, 1);
 501                 lua_pushnil(L);
 502                 lua_pushinteger(L, rv);
 503                 return 2;
 504         }
 505
 506         return 1;
 507 }
 508
 509
 510 static void
 511 ubus_lua_call_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 512 {
 513         lua_State *L = (lua_State *)req->priv;
 514
 515         if (!msg)
 516                 lua_pushnil(L);
 517
 518         ubus_lua_parse_blob_array(L, blob_data(msg), blob_len(msg), true);
 519 }
 520
 521 static int
 522 ubus_lua_call(lua_State *L)
 523 {
 524         int rv, top;
 525         uint32_t id;
 526         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 527         const char *path = luaL_checkstring(L, 2);
 528         const char *func = luaL_checkstring(L, 3);
 529
 530         luaL_checktype(L, 4, LUA_TTABLE);
 531         blob_buf_init(&c->buf, 0);
 532
 533         if (!ubus_lua_format_blob_array(L, &c->buf, true))
 534         {
 535                 lua_pushnil(L);
 536                 lua_pushinteger(L, UBUS_STATUS_INVALID_ARGUMENT);
 537                 return 2;
 538         }
 539
 540         rv = ubus_lookup_id(c->ctx, path, &id);
 541
 542         if (rv)
 543         {
 544                 lua_pushnil(L);
 545                 lua_pushinteger(L, rv);
 546                 return 2;
 547         }
 548
 549         top = lua_gettop(L);
 550         rv = ubus_invoke(c->ctx, id, func, c->buf.head, ubus_lua_call_cb, L, c->timeout * 1000);
 551
 552         if (rv != UBUS_STATUS_OK)
 553         {
 554                 lua_pop(L, 1);
 555                 lua_pushnil(L);
 556                 lua_pushinteger(L, rv);
 557                 return 2;
 558         }
 559
 560         return lua_gettop(L) - top;
 561 }
 562
 563
 564 static int
 565 ubus_lua__gc(lua_State *L)
 566 {
 567         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 568
 569         if (c->ctx != NULL)
 570         {
 571                 ubus_free(c->ctx);
 572                 memset(c, 0, sizeof(*c));
 573         }
 574
 575         return 0;
 576 }
 577
 578 static const luaL_Reg ubus[] = {
 579         { "connect", ubus_lua_connect },
 580         { "objects", ubus_lua_objects },
 581         { "add", ubus_lua_add },
 582         { "reply", ubus_lua_reply },
 583         { "signatures", ubus_lua_signatures },
 584         { "call", ubus_lua_call },
 585         { "close", ubus_lua__gc },
 586         { "__gc", ubus_lua__gc },
 587         { NULL, NULL },
 588 };
 589
 590 /* avoid missing prototype warning */
 591 int luaopen_ubus(lua_State *L);
 592
 593 int
 594 luaopen_ubus(lua_State *L)
 595 {
 596         /* create metatable */
 597         luaL_newmetatable(L, METANAME);
 598
 599         /* metatable.__index = metatable */
 600         lua_pushvalue(L, -1);
 601         lua_setfield(L, -2, "__index");
 602
 603         /* fill metatable */
 604         luaL_register(L, NULL, ubus);
 605         lua_pop(L, 1);
 606
 607         /* create module */
 608         luaL_register(L, MODNAME, ubus);
 609
 610         /* set some enum defines */
 611         lua_pushinteger(L, BLOBMSG_TYPE_ARRAY);
 612         lua_setfield(L, -2, "ARRAY");
 613         lua_pushinteger(L, BLOBMSG_TYPE_TABLE);
 614         lua_setfield(L, -2, "TABLE");
 615         lua_pushinteger(L, BLOBMSG_TYPE_STRING);
 616         lua_setfield(L, -2, "STRING");
 617         lua_pushinteger(L, BLOBMSG_TYPE_INT64);
 618         lua_setfield(L, -2, "INT64");
 619         lua_pushinteger(L, BLOBMSG_TYPE_INT32);
 620         lua_setfield(L, -2, "INT32");
 621         lua_pushinteger(L, BLOBMSG_TYPE_INT16);
 622         lua_setfield(L, -2, "INT16");
 623         lua_pushinteger(L, BLOBMSG_TYPE_INT8);
 624         lua_setfield(L, -2, "INT8");
 625         lua_pushinteger(L, BLOBMSG_TYPE_BOOL);
 626         lua_setfield(L, -2, "BOOLEAN");
 627
 628         /* used in our callbacks */
 629         state = L;
 630
 631         /* create the callback table */
 632         lua_createtable(L, 1, 0);
 633         lua_setglobal(L, "__ubus_cb");
 634
 635         return 0;
 636 }